Hello, Maybe functions "xts", "endpoints" and "period.apply" of the "xts" package might help you.
Regards, Pascal On Fri, Feb 28, 2014 at 1:32 AM, Yang Yang <simonyangy...@gmail.com> wrote: > Hi > > Currently I am working on a river discharge data analysis. I have the daily > discharge record from 1935 to now. I want to extract the annual maximum > discharge for each hydrolocial year (*start from 01/11 to next year 31/10*). > However, I found that the hydroTSM package can only deal with the natural > year. I tried to use the "zoo" package, but I found it's difficult to > compute, as each year have different days. Does anyone have some idea? > Thanks. > > the data looks like: > > 01-11-1935 66302-11-1935 59603-11-1935 45004-11-1935 38105-11-1935 > 35406-11-1935 312 > > my code: > > mydata<-read.table("discharge") > colnames(mydata) <- c("date","discharge") > > library(zoo) > z<-zooreg(mydata[,2],start=as.Date("1935-11-1")) > > mydta$date <- as.POSIXct(dat$date) > > q.month<-daily2monthly(z,FUN=max,na.rm = TRUE,date.fmt = > "%Y-%m-%d",out.fmt="numeric") > q.month.plain=coredata(q.month) > > z.month<-zooreg(q.month.plain,start=1,frequency=12) > > Thanks very much. > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. -- Pascal Oettli Project Scientist JAMSTEC Yokohama, Japan ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.